HAEMATOLOGICAL CHANGES ACCOMPANYING PROLONGED OCULAR CHLORAMPHENICOL ADMINISTRATION IN LABORATORY RABBITS.

Abstract

The toxic effect of ocular chloramphenicol on haematological parameters was 
studied in laboratory rabbits; Oryctolagus cuniculus while the haemotoxic effect of 
oral chloramphenicol provided the basis for comparison. 20 adult male rabbits 
were randomly but equally divided into two main groups based on the route of 
administration of the drug (i.e ocular or oral). In each group of ten rabbits equal 
number of rabbits were randomly divided into test (n=5) and control (n=5) 
subgroups. Oral chloramphenicol was administered at a dosage of 500mg twice 
daily for 21 days. Drops of ocular chloramphenicol were administered on the 
conjunctiva of the animals thrice daily over the same period of time. The control 
animals were administered with 0.9% physiological saline orally and distilled water 
administered ocularly. Ocular chloramphenicol produced no significant changes in 
the haematological parameters evaluated on the 11th and 22nd days. Conversely 
oral chloramphenicol was observed to significantly (P<0.05) reduced the mean total 
erythrocyte count, PCV, mean corpuscular haemoglobin, and neutrophils 
progressively by the 11th and 22nd days. Ocular chloramphenicol was confirmed to 
have no dose-dependent haemotoxic effect however the possibility of idiosyncratic 
aplastic anaemia is highlighted in this study.